NGC 2020

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Emission nebula
NGC 2020

Left NGC 2020 (bluish) and the star cluster NGC 2014 accompanied by a reddish nebula in an image taken by the Hubble Space Telescope

Left NGC 2020 (bluish) and the star cluster NGC 2014 accompanied by a reddish nebula in an image taken by the Hubble Space Telescope
AladinLite
Constellation Swordfish
Position
equinox :  J2000.0 , epoch : J2000.0
Right ascension 05 h 33 m 12.6 s
declination -67 ° 42 ′ 57 ″
Appearance

Angular expansion 2.0 
Ionizing source
designation Brey 48 
Type WR4 + O8 
Physical data

Affiliation Large Magellanic Cloud 
diameter 163 ly
history

discovery John Herschel
Date of discovery December 30, 1836
Catalog names
 NGC  2020 •  GC  1223 •  h  2903 • ESO 56-? 148

NGC 2020 is an HII region in the constellation Swordfish , inside of which a Wolf-Rayet Ring Nebula has formed around the Wolf-Rayet star Brey 48. It lies at a distance of 160,000 light years and belongs to the Large Magellanic Cloud . The color difference between NGC 2020 and NGC 2014 is due to the presence of Brey 48. Its high effective temperature ensures a high intensity of the doubly ionized oxygen line at 500.7 nm, which is shown in blue in the picture. The glow of the HII area NGC 2014, on the other hand, is dominated by the red-colored recombination line of the excited hydrogen at 656.3 nm ( Hα ).

The nebula was discovered by astronomer John Herschel on December 30, 1836 , but may have been observed by James Dunlop as early as 1826 .

Individual evidence

  1. ↑ NASA / IPAC EXTRAGALACTIC DATABASE.
  2. ↑ SEDS : Revised NGC Data for NGC 2020.
  3. ↑ a b c Y.-H. Chu, K. Weis, DR Garnett: Physical Structure of Small Wolf-Rayet Ring Nebulae . In: The Astronomical Journal . tape 117 , no. 3 , 1999, p. 1433–1440 , doi : 10.1086 / 300777 , arxiv : astro-ph / 9812076 , bibcode : 1999AJ .... 117.1433C .
  4. ↑ C. Foellmi, AFJ Moffat, MA Guerrero: Wolf-Rayet star binaries massive-evolution in the Magellanic Clouds and implications for - II Large Magellanic Cloud. . In: Monthly Notice of the Royal Astronomical Society . tape 338 , no. 4 , 2003, p. 1025-1056 , doi : 10.1046 / j.1365-8711.2003.06161.x , bibcode : 2003MNRAS.338.1025F .
  5. ^ MA Dopita, JF Bell, Y.-H. Chu, TA Lozinskaya: An atlas of the interstellar environment of Wolf-Rayet stars in the Magellanic clouds . In: The Astrophysical Journal: Supplement Series . tape 93 , no. 2 , 1994, p. 455-463 , bibcode : 1994ApJS ... 93..455D .
  6. ↑ New General Catalog Objects: NGC 2000-2049 | NGC 2020 (an EN in the Large Magellanic Cloud). In: Seligman. March 13, 2020, accessed April 25, 2020 .